Black azo dye and process of making same.



UNITED STATES PATENT FFICE.

KARL SCHIRMAOHER, OF H O CHST-ON-THE-MAIN, GERMAN Y, ASSIGNOR TO THE FARBWERKE, VORMALS MEISTER, LUOIUS & BRUNING, OF SAME PLACE.

BLACK AZO DYE AND PROCESS-OF MAKING SAME.

SPECIFICATION formingpart of Letters Patent No. 627,783, dated June 27, 1899.

Application filed October 3 1, 1 89 8.

To all whom it may concern:

Be it known that I, KARL SOHIRMACHER, doctor of philosophy, a citizen of the Empire of Germany, residing at Hochst-on-the-Main,

Germany, have in vented certain new anduseful Improvements in the Manufacture of Black Monoazo Dyestuffs, of which the following is a specification.

I have found that by the treatment of diazotized picramic acid with naphtholsulfonic acids which are amidated lnonoazo dyestuffs maybe produced which dye wool direct black or on subsequent treatment with chromates and are characterized by their fastness and I 5 property of dyeing evenly.

As amidated naphtholsulfonic acids may be, for instance,-employed: 2:8:6; 128:4; 1:5 :7 2: 5: 7 amidonaphtholsulfonic acids; 1: 8: 3: 6; 2 8 z 3: 6; 1: 8 z 4: 6 amidonaphtholdisulfonic 2o acids; 2:5: 7 ethylamidonaphtholsulfonic. acid 1 8: 3 i 6 ethylamidonaphtholdisulfonic acid; 1:5:2z7 and 1:3:6z8 diamidonaphtholsulfonic acids.

I illustrate my process by the following ex-' ample: 22.2 kilos of sodium salt of picramic acid are dissolved in water, to which are added 6.9 kilos of nitrite. This solution is run into a mixture of forty kilos of hydrochloric acid and one hundred kilos of ice-water, the whole 0 beingstirredforashorttime. Thediazo compound separates out mostly in yellow-green crystals. If this solution be run into a solution of 34.2 kilos of amidonaphthol disulfonic acid H and thirty kilos of soda in water,

3 5 the mass becomes blue-red,'and the resulting dyestuif separates out in laminae of bronze luster. To complete the reaction, the mixture is well stirred during six hours. It is then heated to 100 centigrade and salted out.

- 0 When dried, the dyestuff is in the form of a Serial No. 695 ,004. (Specimens) black powder of bronze luster, soluble in water with a red-blue color.

The dyestuif dyes wool in an acid-bath in blue-black shades, which on a subsequent treatment with bichromate become deep green, very fast to washing, soap, and f ulliug.

Having now described my invention, what I claim is 1. The process for the manufacture of a black dyeing monoazo d yestuif which consists in treating diazotized picramic acid withnaphtholsulfonic acids containing amido groups, substantially as described.

' 2. Process for the manufacture of a black dyeing monoazodyestufi which consists inallowing dlazotized picramic acid to act upon 1:8:326 amidonaphtholdisulfonic acid H, substantially as described.

3. As a new product,the black dyeing monoazo dyestuff from diazotized picramic acid and naphtholsulfonic acids containing amido groups, being adark-black powder, soluble in water, insoluble in alcohol, benzene or petroleum, soluble in concentrated sulfuric acid with a red color.

4. As new product, the black dyeing monoazo d yestuff from diazotized picramic acid and 1: 8: 3: 6 amidonaphtholdisulfonic acid, being a black powder of greenish luster soluble in hot water, insoluble in alcohol, benzene, petroleum and soluble in concentrated sulfuric acid with a red color.

In testimony that I claim the foregoing as my invention I have signed my name in presence of two subscribing witnesses.

KARL soI-nRMAonER;

Witnesses HEINRICH HAHN, ALFRED BRISBOIS. 

